mc33468sn-20atr ON Semiconductor, mc33468sn-20atr Datasheet - Page 5

• Manufacturer Part Number: mc33468sn-20atr
• Description: Variable Frequency Micropower Dc-to-dc Converter
• Manufacturer: ON Semiconductor

obtained by using a MOSFET as the switch transistor, in
which no gate resistor or capacitor is needed.
capacitor voltage is higher than V out . Select an inductor with
low DC resistance and high saturation. A Schottky diode is
recommended for a lower voltage drop and faster switching.
MOTOROLA ANALOG IC DEVICE DATA
If input voltage is high enough, higher efficiency may be
When choosing the output capacitor, ensure that the
V IN
V IN
Figure 7. Typical Application for Output Voltages Over 2.0 V
L1
Q1
Figure 6. Typical 2.0 V Application with MOSFET
Inductor (L1)
Diode (D1)
Capacitor (C OUT )
Transistor (Q1)
Resistor (R1)
Resistor (R2)
MC33468
D1
EXT
V DD
EXT
V DD
CD54 (15
MBRD540T1
47
MMFT3055VL
150 k
10 k
high enough to allow for spikes in voltage.
Use external resistors that are much smaller resistance than
the resistance internal to the I C (minimum of 2 M
is much less than the internal resistance, the error is
minimized.
GND
GND
m
W
F (Tantalum type)
V OUT
V OUT
MOSFET and BJT voltage rating (V DS and V CE ) should be
W
m
H)
(2.0 V)
R1
R2
C OUT
V OUT
V OUT
W
). When R1
5